Food and Focus: The Complex Link Between Diet and ADHD

    Posted on September 26, 2024

    Written by: Marci Clow, MS, RDN


    Although food does not cause, nor can it cure, attention-deficit/hyperactivity disorder (ADHD), poor dietary and lifestyle habits can contribute to ADHD symptoms and severity. Just like cars need high-quality gas to keep them functioning at a prime, all humans, including those with ADHD, need a balanced, wholesome diet to adequately fuel both physical and mental health. While much still needs to be learned, this article will help to unveil the complex link between diet and ADHD.

    The Brain-Food Connection

    Attention-deficit/hyperactivity disorder, known as ADHD, is a neurodevelopmental condition often diagnosed in childhood with symptoms such as inattention, hyperactivity, and impulsivity that can persist into adulthood. In adults, ADHD tends to be internalized, presenting with issues such as scattered thoughts, poor time management, and restlessness. In individuals with ADHD, dopamine and serotonin activity, the brain chemicals known as neurotransmitters, is altered, making it difficult to control behaviors.

    How does nutrition impact brain function?

    If your diet is poor, it can affect the output/function of your brain and overall health and well-being. Research has linked the severity of ADHD symptoms to low-quality diets and low blood levels of certain nutrients. A consistent and balanced intake of healthy foods and adequate hydration is necessary for optimal brain functioning and can positively influence common symptoms associated with ADHD, including energy levels, improved focus, and less irritability.

    What are the key nutrients that have a potential role in ADHD management?
    Although all nutrients have a unique role in human health, there are a few that might be considered to have a particularly important role in ADHD because of how they affect brain or neurologic function:


    Vitamin D: Key areas of the brain that are implicated in ADHD are known to contain vitamin D receptors, and the importance of vitamin D in brain development and health continues to evolve in the research. Individuals with ADHD are often deficient in vitamin D. Foods naturally containing vitamin D are limited to fatty fish, egg yolks, fortified foods, and a small amount of other animal source foods. Vitamin D can also be made in the body with regular exposure to the sun.
    Iron: Necessary for transporting oxygen in the blood to all areas of the body, including the brain; low iron levels have been linked to reduced cognitive function and other ADHD symptoms. Iron is found in meat, beans, tofu, dark leafy greens, and fortified foods like cereal.

    Did you know?: Low iron levels can mimic some of the symptoms of ADHD related to difficulties concentrating, so it is important to have your healthcare provider screen iron levels. Before taking an iron or any supplement, first check with your provider; too much may be harmful.
    Magnesium: Magnesium deficiency has been linked to hyperactivity and impulsivity. Magnesium is found in foods such as nuts and seeds, legumes, whole grains, and green leafy vegetables.

    Zinc: In regard to brain health, zinc is necessary for the transport of and improving the brain’s response to dopamine. Deficiencies can result in symptoms of inattention. Zinc naturally occurs in shellfish, meat, whole grains, and beans.
    Omega-3s: The omega-3 fatty acids EPA and DHA play a role in neurotransmitter function. Studies have shown that an increased intake may help stabilize symptoms associated with ADHD, like inattention and hyperactivity. The predominant dietary sources of omega-3s are salmon, cold-water white fish, eggs from chickens fed enriched grain, certain nuts and seeds like walnuts and flax seeds, or foods like plant-based beverages fortified with omega-3s from algae. If you do not consume fish regularly, an omega-3 supplement with a direct source of EPA and DHA, like those offered by ÖRLÖ, can support your omega-3 essential fatty acid needs.

    What Foods May Worsen ADHD Symptoms?

    A common dietary pattern of many Americans includes ultra-processed foods. Many of these are not only loaded with ingredients that have been linked to ADHD symptoms but also have poor overall nutritional value. Some individuals with ADHD may tolerate certain foods and/or additives, whereas others may find those same ingredients worsen symptoms and need to be avoided. Elimination diets in which certain foods or additives are removed from the diet and then gradually reintroduced may be recommended by your healthcare professional. Be cautious of adhering to a highly restrictive diet based on hearsay, as many do not have solid evidence to back them up. Removing sugar-sweetened beverages, candy, colorful snack foods and cereals, dairy, gluten, and other foods that contain the following may help ADHD symptoms:


    Sugar: Although studies on sugar intake and its effect on ADHD have had conflicting results, foods that are higher in sugar cause an immediate spike in blood sugar followed by a significant drop; these highs and lows can impact focus, energy, and mood. Simply speaking, for those with ADHD, it is a good idea to monitor sugar intake as it might make symptoms worse.
    Did you know?: There are more than 50 synonyms for ingredients that are essentially the same as sugar. Some of the most commonly seen on labels are corn syrup/sweetener, dehydrated cane juice, dextrin/dextrose, maltose, rice syrup, fructose, and sucrose.

    Artificial sweeteners: You might be surprised to learn that artificial sweeteners can actually worsen sugar cravings. Those with saccharin (Sweet’N Low®) and Aspartame (Equal®, Nutrasweet®) have been suggested to negatively affect certain individuals with ADHD.

    Food dyes/flavorings: The research is also mixed on whether or not ADHD symptoms are worsened by artificial food colors. Food dyes can trigger allergic responses and migraines and have been linked to an increase in ADHD symptoms in sensitive individuals. In fact, artificial food colors are banned in some European countries because of the suggested negative behavioral effects in children. Artificial colors are often used with artificial flavorings in candy, juice, soda, and ultra-processed snack foods.

    Preservatives and flavor enhancers: Preservatives like nitrates, nitrites, sulfates, and sodium benzoate and flavor enhancers like MSG may also worsen ADHD symptoms. Nitrites and nitrates are found in almost all processed meats, and sodium benzoate is typically added to soda, fruit juices, and margarine. It appears that there is a high level of variance in response to these additives, and further research is needed to assess if avoiding them could be beneficial for individuals with ADHD.

    Caffeine: As a stimulant, caffeine can mimic or worsen ADHD symptoms in sensitive individuals, especially children, and can lead to sleep problems, which are also correlated with ADHD. Some medications used to treat ADHD contain stimulants that should not be combined with caffeine. Foods/beverages that may unknowingly be sources of caffeine include colas, energy drinks, some types of snack bars, chocolate, and tea.

    Practical tip: It is important to look closely at the ingredient lists on food labels to identify the presence of the foods and additives mentioned here that may worsen ADHD symptoms in certain individuals.

    Foods That May Improve ADHD Symptoms

    Consuming healthy, balanced meals throughout the day helps to minimize lows and highs in blood sugar and can ease ADHD symptoms. Research suggests that a simple diet that emphasizes fruits, vegetables, whole grains, and lean protein is suitable for individuals with ADHD and can prevent overconsumption of foods with low nutritional value. However, many dietary strategies and particular foods have been suggested to improve ADHD symptoms. Balanced is a word that gets thrown around a lot when it comes to choosing foods, but what does it really mean in the context of ADHD? As part of a plan to help to stave off ADHD symptoms, meals and snacks should be balanced with a high-fiber carbohydrate source, protein source, and healthy fat for meals or snacks. Using this concept can simplify meal planning and help with focus and energy throughout the day. Let’s explore:


    Fiber-rich carbohydrates: Carbohydrates provide glucose, which is the main fuel source our cells use for energy; we all need them. Sugary and starchy foods with low fiber, such as white bread, doughnuts, and sodas, are known as simple carbs; they are digested quickly and will make blood sugar spike higher and faster. Whereas foods with fiber-rich carbohydrates (aka complex carbs) are digested slower because they contain starch and fiber, allowing for a gradual release of glucose into the bloodstream. Fiber-rich complex carbs provide a steady release of energy, helping individuals with ADHD avoid blood sugar highs and lows and maintain focus. Fiber-rich carbs include foods like fruits, vegetables, beans, and whole grains.

    Protein: Protein has many functions in the body, including helping you feel full longer and maintain consistent blood sugar levels. One essential role related to ADHD is that protein provides the body with amino acids, which are used to make the neurotransmitters that play key roles in focus and concentration. Good protein sources include nuts, seeds, tofu, lentils, beans, eggs, dairy, poultry, fish, and lean beef or pork.

    Healthy fats: Fats make up part of the tissues of the brain; they have many functions, including protecting organs and aiding the absorption of fat-soluble vitamins from food. Like protein, fats also help keep you full and delay the absorption of carbs into your bloodstream. Sources of healthy fats include avocado, nuts and nut butter, seeds, olive oil, and fatty fish.

    Here are a few examples of ADHD-friendly meal/snack ideas that incorporate the balanced ADHD meal-planning concept:

    1. Greek yogurt topped with nuts and berries.
    2. Whole-wheat avocado toast with sliced tomato and a poached egg.
    3. Apple slices or celery sticks with nut butter.
    4. A hard-boiled or deviled egg, whole-grain crackers, and a handful of grapes.
    5. Customize your own trail mix with nuts, seeds, dark chocolate chips, and dried fruit.
    6. Grilled salmon filet with brown rice and roasted broccoli florets.


    Practical tips to ensure you have ADHD-friendly snacks on hand:
    Spend 30 minutes each week to prep and portion out snacks ahead of time
    Keep a healthy snack attack stash in your car, gym bag, or desk at work

    Individualized Nutrition for ADHD

    There is definitely not a one-size-fits-all set of dietary guidelines when it comes to ADHD. However, what does appear to be universal is that nutrition plays an important role in fueling the ADHD brain, particularly when it comes to managing blood sugar highs and lows associated with behavioral patterns. It is crucial for those with ADHD to work with a healthcare professional, such as a registered dietitian, and experiment with different foods to identify likes/dislikes, detect food sensitivities, and create a personalized, sustainable meal plan that is customized for their needs and symptoms.

    Beyond Food: The Role of Lifestyle in ADHD Management

    Food is just one piece of the puzzle when it comes to managing ADHD. In addition to a healthy, balanced diet, a comprehensive plan to manage ADHD should include consideration of lifestyle factors, such as adequate sleep, regular exercise, and stress management, in addition to behavioral therapy, medication, and/or supplements, if recommended by a healthcare practitioner. Researchers have found more screen time and less physical activity to be factors associated with ADHD symptoms, linking an increase in exercise to enhanced neurotransmitter activity.


    Key Takeaways:

    A dietary pattern that includes a wide variety of fresh fruits and vegetables, fiber-rich carbohydrates, lean proteins, and healthy fats is a good starting point for managing symptoms associated with ADHD. Consume balanced meals and snacks at regular intervals throughout the day to help avoid blood sugar highs and lows, which have been linked to inattention, hyperactivity, and impulsivity in people with ADHD. Work with a healthcare professional, such as a registered dietitian, who is well-versed in lifestyle and dietary factors that impact ADHD to help establish a routine and personalize a plan suited to individual needs.


    Additional Information and Resources

     

    Note: The information presented in this article is for general educational purposes only and is not a substitute for medical advice. For a personalized plan, please consult with your health care provider or a registered dietitian.


    References


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    Del-Ponte B, Quinte GC, Cruz S, et al. Dietary patterns and attention deficit/hyperactivity disorder (ADHD): A systematic review and meta-analysis. J Affect Disord. 2019 ;252:160-173. doi:10.1016/j.jad.2019.04.061

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    Lepping P, Huber M. Role of zinc in the pathogenesis of attention-deficit hyperactivity disorder: implications for research and treatment. CNS Drugs. 2010;24(9):721-728. doi:10.2165/11537610-000000000-00000

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    National Institute of Mental Health. Attention-Deficit/Hyperactivity Disorder. U.S. Department of Health and Human Services, National Institutes of Health. Updated September 2023. Accessed August 28, 2024. https://www.nimh.nih.gov/health/topics/attention-deficit-hyperactivity-disorder-adhd

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    Marci Clow is a registered dietitian nutritionist and the founder of Clowt Content, an organization which provides evidence-based content on a wide range of food and nutrition topics. The information presented here is intended only to be educational and provide readers with information; it is not an endorsement of the writer for any particular product. These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease.

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